Permanent mold machine



PERMANENT MOLD MACHINE Filed April 21, 1938 3 Sheets-Sheet l INVENTOR BY 2 V g "j7 A TTORNE Y6 Oct. 29, 1940. L DQSTAL 7 2,219,864

PERMANENT MOLD MACHINE Filed April 21, 1938 3 Sheets-Sheet 2 11v VENTOR Jig/v? 1 fioJZaZ 4 TORNE Y0 Oct. 29,1940. J. AL I 2,219,864

PERMANENT MOLD MACHINE Filed April 21, 1938 3 Sheets-Sheet 3 A TORNEYS Pmmdoa. 29, 1940 PATENT, OFFICE PERMANENT MOLD MACHINE Joseph L. Dostal, Birmingham, Mich., assignor to Eaton Manufacturing company, Cleveland, Ohio, a corporation of Ohio Application April 21, 1938, Serial No. 203,255

3 Claims. (Cl. 22-177) This invention relates to permanent molds and to machines for use in connection therewith in the casting of molten metals, the principal object being the provision of apparatus of this type 5 of improved efficiency and construction.

Objects of the invention include the provision of a permanent mold apparatus, including a mold and associated structure, having provisions for the eificient cooling of the same whereby to en- 1 able the length of time between successive casting operations to be shortened; the provision of a permanent casting mold apparatus providing for the flow of air over the surfaces thereof heated in the casting operation in such a manner as to efliciently dissipate the heat absorbed by the mold in the casting operation; the provision of a permanent mold apparatus as above described so constructed and arranged as to apply the cooling air first to that portion of the mold where the concentration of heat in the casting operation is the greatest; the provision of an apparatus as above described having provisions for modifying the flow of cooling air into contact with the mold part to better accommodate the particular size, shape and/or contour of the mold as governed by the parts to be cast therein; and the provision of a permanent m'old apparatus arranged for the circulation of air over the rear faces of the molds for the purpose of cooling the molds, in combination with suitable baiile means adjustably related with respect thereto whereby to enable distribution of the air flowing through the mold to obtain optimum cooling conditions.

Other objects of the invention include the provision 'of means for supporting one part of a multi-part permanent mold structure so as to enable it to be readily advanced toward or retracted from a cooperating portion; the provision of power means for moving one portion of 40 a permanent mold into and out of cooperative relation with respect to another portion thereof together with means for supporting the movable portion of the mold for such movement in such a manner as to insure its freedom from binding or 5 the like during such movement; the provision of means for supporting one portion of a permanent mold for movement towards and from a cooperating portion and power means for effecting such movement, the connection with the power means so being such as to eliminate the necessity of accurate manufacture and assembly between the power means and the possibility of binding occurring because of wear of the supporting means; and the provision of a permanent mold including 55 a pair of separable portions and a cooperating vof the permanent'mold parts in face elevation track. one of the mold portions being wholly supported on the track and being movable-thereon into and out of cooperative relation with the other of said portions by power means.

Further objects of the invention include the 5 provision of a permanent mold casting machine having certain new and novel features of construction; the provision of a permanent mold casting machine having a constant speed motor for effecting rotation thereof and means in the m connection between the motor and the movable part of the machine enabling the rate of rotation of the machine to be varied at will; and the provision of a permanent mold casting machine particularly designed to permit a relatively high rate 15 of production thereby.

The above being among the objects of the present inventionthe same consists in certain novel features of construction and .combinations of parts to be hereinafter described with reference 20 to the accompanying drawings, and then claimed, having the above and other objects in view.

In the accompanying drawings which illustrate a suitable embodiment of the present invention and in which like numerals refer to like parts 25 throughout the several different views,

Fig. 1 is a fragmentary top plan view of a permanent mold machine embodying the present invention;

Fig. 2 is a fragmentary vertical sectional view 30 taken axially through the permanent mold machine illustrated in Fig. 1;

Fig. 3 is an enlarged horizontal sectional view through one of the permanent molds and taken as on the line 3-3 of Fig. 2; 35

Fig. 4 is a vertical sectional view taken on the line 4-4 of Fig. 3;

Fig. 5 is a partially broken vertical sectional view taken on the line 5-5 of Fig. 4, showing one Fig. 61s a vertical sectional view taken on the line 6-6 of Fig. 3;

Fig. 7 is an enlarged vertical sectional view taken on the line |l of Fig. 1; and v Fig. 8 is a partially broken perspective view of an article of the type formed by the particular conformation of the molds shown by way-of illustration.

Permanent mold machines such as contemplated by the present invention comprises a relatively large generally circular supporting frame structure or turret suitably supported for rotation about its axis which is vertically disposed and provided with suitable means for rotating the same. At usually uniformly spaced stations adg jacent the periphery of the turret a permanent mold unit is provided and these units, of course, rotate with the turret. Each permanent mold unit includes a plurality, and usually two, mold sections which cooperate with each other to form scribed as may be necessary to accommodate the same will be apparent to those skilled in the art. It will also be understood by those skilled in the art that in the broader aspects of the present invention permanent mold units of the type provided by the present invention may be employed separately from a permanent molding machine of the type shown and described which includes a plurality of such units, as the novel features of the units, each of which includes molds and cooperating supports, themselves are of advantage whether or not the units are arranged and operated singly or are arranged and operated in groups as herein described.

Each permanent mold comprises a relatively fixed part or half fixed with respect to the rotatable turret of a permanent mold machine of the type herein described although bodily rotatable therewith, anda cooperating part or half movable with respect thereto, the two parts cooperating with one another to form a mold cavity of the desired character between them. When such molds are employed in conjunction with a molding machine of the type herein described means are provided for maintaining the two halves of each mold in cooperating contacting 40 relationship during a portion of each rotation of the turret and to separate the mold halves during another portion of each complete rotation of the turret. The molds are poured during that portion of each rotation of the turret when the 45 halves are maintained in contact with each other and are separated from one another after the metal poured has solidified sufficiently to permit removal of the object cast from the mold without undue danger of distortion, and the halves are 50 maintained in separated relation until a point -55 towards and fromits cooperating half.

in the rotation of the turret immediately preceding the point at which the molds are poured. Means are provided for automatically advancing and retracting the movable half of each mold Additionally the mold halves are each so constructed and cooperating means provided in conjunctiontherewith that air is caused to continually flow over the rear faces of the mold halvesfor the o purpose of extracting the heat therefrom so as to 65 sible.

prevent the molds from becoming over-heated, toeffect a quicker solidification of the metal cast therein, and to permit operation of the machine at a greater speed than would otherwise be pos- The means thus provided will hereafter be described in detail later.

Referring now to the drawings and particularly to Figs. 1 and 2 the permanent mold machine there shown includes a suitable fixed supporting 70 base or structure indicated generally at l0 and as provided with a fixed vertically extending cylindrical post or stub shaft l2. Rotatably mounted upon the post I2 is a drum-like member l4 which forms the central member of the ro- 75 tatable turret and which is provided with a suitably bushed central hub l6 which rotatably receives the post 12 for guiding the drum member M in its rotating movement. Suitable thrust bearing elements 18 disposed between the drum member [4 andthe supporting base I0 serve to take the thrust of the turret.

A plurality of radially extending equally angularly, spaced supporting arms 20 are rigidly secured to the peripheral surface of the drums l4 and project radially outwardly therefrom. At their outer ends the arms 20 are jointed by cord members 22 which thus serve to provide with the drum I4 and arms 20 a more ,or less circular radially spoked frame structure. The arms 20 are hollow and the hollow interiors are in open communication with the interior of the drum member l4. The upper end of the drum member I4 has suitably secured to its upper edge an annular plate-like member 24 which extends radially inwardly from the outer edge thereof. Adjacent its inner edge the plate member 24 has secured thereto and supports an upwardly extending circular housing 26 which housing is provided with an annular cored passage 28 therein serving as a distributing duct for compressed air as will hereinafter be more specifically brought out.

The upper. end of the hub 16 of the drum-like member I4 is closed bya cap member 30 the interior of which is divided into completely separated upper and lower chambers by means of a cross-wall 32. Means such as the tube 34 are provided for introducing lubricant into the interior of the lower chamber so as to effect lubrication of the wearing surfaces of the post l2 and the thrust bearing l8. Suitable means such as the connection 36 communicating with the interior of the upper chamber in the cap 30 is suitably connected by means of a pipe line 3'! (see 'Fig. 1) to the interior of the duct 28 in the member 23. Such upper chamber also communicates through the central upwardly extending connection 38 with a swivel joint 40 which is connected by a tube 42 with a suitable source of compressed air or suitable motive fluid. The air thus delivered through the pipe 42 passes through the swivel connection 40 into the upper chamber in the cap or cover 30 and then through the connection 36 and pipe line 31 to the interior of the annular conduit 28 in the member 26 to be there distributed through the various valves hereinafter to be described for use in the operation of the movable sections of the various permament molds. I

Suitably rotatably supported upon the upper end of the cap 30 is a spider 44 which terminates at its periphery in a ring 46 the lower edge of which is so constructed and arranged as to cooperate with the upper edge of the housing member 26 so as to minimize the leakage of air therebetween. The upper edge of the ring 45 is adapted to receive a stack or flue 48 through which air employed in the cooling of the mold may be withdrawn. It will be understood that the spider 44, ring 46 and flue or stack 48 remains stationary during rotation of the turret.

In order to rotate the turret the lower face of the drum member l4 has concentrically secured thereto an internal gear 50. A transmission mechanism including a casing 52 rigidly fixed with respect to the base l0 and a spur gear 54 lying in mesh with the gear 50 is employed for rotating the turret. The gear 54 is fixed upon a vertical shaft 58 rotatably mounted in the easing 52 and within which has fixed thereto a ring gear 58. The ring gear 58 lies in mesh with a pinion 60 fixed upon the horizontally extending shaft 62 which isrotatably mounted within the casing 52 and one end of which projects therefrom and receives thereon a coupling member 60. The

coupling member 84 is employed for connecting the shaft 62 to one element of a variable speed device of known construction including the elements 60 and 68 which are suitably connected turret being governed by the usual adjusting means provided in connection with the speed reducing'unit 66,'58. The necessity for adjusting thespeed'of rotation of the turret occurs as aresult of the fact that it is always desirable to operate the turret at the highest speed possible consistent with the desired quality of work produced by the machine, this speed usually varying in accordance with the size of the particular articles being cast in the machine, the smaller the article the quicker it may be poured and the quicker it will cool to such an extent as to permit its discharge from the-machine, as will be readily understood by thos "skilled in the art.

A mold assembly or unit, each including a pair of mold parts/supports and other elements aiding in propping a complete operative assemblage, is supper ed between theouter ends of each ad- 40 jacentpair of arms 20, all of these assemblies or units being identical and the showing and description of one being sufiicient as the showing and description of. all. Each mold-assembly includes a section fixed with respect to the turrets and a part movable with respect to the turrets and each mold proper includes, in the particular embodiment illustrated, a mold half 14 fixed with respect to the fixed section of the mold and a mold half I8 fixed with respect to the movable section of the mold, the mold halves I4 and I8 cooperating to form between them a depression or cavity 71 of the desired size, shape and contour desired in the particular article to be cast. The mold half I4 is fixed by means of bolts I8 to a vertically extending support indicated generally at preferably formed integrally with the corresponding cord 22. Likewise the mold half I6 is-fixed by means of bolts 82 to a support indicated generally at 84.

The support 84 is fixed as by bolts 86 to the upwardly extending flange 88 of a carriage including a pair of spaced parallel arms 90 arranged in generally radial relation with respect ,to the axis of rotation of the turret and the outer and inner ends of each of which each rotatably supports a grooved roller 92. The grooved rollers 92 at each side of the carriage 90 are received upon corresponding rails 94, the rails 94 being parallel and arranged with the center line between them in radial relation with respect to the axis of rotation of the turret. The rails 94 are supported from the arms 20 by means of a plurality of cross-bars 98 extending between and fixed to, the lower faces of the cooperating pair of arms 20.

Each movable mold section including a support and except at its 84 and cooperating mold half I6 is thus arranged for bodily shlftable movement towards and away from the cooperating mold half I4 and support 82 and the entire weight of each movable mold section is carried by its corresponding carriage 90 which also serves as the sole means for guiding it through the major portion of its movement to wards and from the fixed mold section. It is, of course, desirable, in order to insure positive alignment of the two mold halves I0 and IS in their closed position in which they cooperate to receive a charge of molten metal, that usual or conventionaldowel pins 98 fixed with respect to one of the mold halves and adapted to be slidably received by the other thereof, be employed in any case, and cooperate during the final closing movement of the die halves to accurately align one with the other.

The supports 80 and 84 are in the main sub stantially similar. In other words each has a substantially plane or fiat, operative face for cooperation with the corresponding mold half It or I6. Each is centrally provided with a relatively large approximately rectangular opening I00 therein as perhaps best brought out in Figs. 5 and 6. Each has a hollow chamber I02 formed along each side thereof which chambers are connected at their lower ends by a hollow crosschamber I04. Each side chamber I02 is provided with a vertically elongated opening I06 extending through the fiat or operative face of the corresponding support.

Clamped between the flat or operative face of each support 80 or 84 and the cooperating mold halves I8 and 16 respectively is a preferably metallic sheet or plate I08 each of which is provided with a vertically elongated opening I09 therein corresponding and registering with each of the corresponding openings I08, and each plate I08 is provided with a vertically elongated central opening 0 therein of preferably greater width than the width of the side openings I09.

The back of each mold half I4 and I8 is hollow marginal edges is spaced from its cooperating plate I08 so as to form a passageway III between each opening IIO and the cooperating openings I09 in each plate I08. in the broader aspectsof the invention it no difference whether the air employed for cooling the molds is forced through the molds under a positive pressure or whether it is drawn through the molds by sub-atmospheric pressure, the latter is preferable in that it aids in reducing the temperature of the air surrounding the molds and, accordingly, it will be assumed in the present case that the air for cooling the molds is drawn through the various passages therefor in the mold sections by suction.

In such case as above described itwill be understood, and as will be hereinafter more fully described, that the cross-passage I04 .in each mold section is connected to a suitable source of suction. In such event this suction will be transmitted from each cross-passage I04 to its cooperating side chambers I02, through the cooperating openings I88 in each of the supports and the cooperating openings I09 in the correspond in'g plate I08 to the space III between the corresponding mold half I4 or I6 and its support 80,0r 84 respectively, and that the suction thus created within these'spaces will cause air to be drawn through the central slot I00 in each of the plates I08, through the various passages described and into the cross-passages or chambers I04 from which it will be discharged.v The air thus flowing a 76 crating openin through the central passages H in the plates I08, in flowing over the rear faces of the mold sections 14 and 18 will extract heat therefrom thereby to effect a cooling of the mold halves. The rate of heat extracted from the mold halves is preferably accelerated by providing a multitude of pins or fins II2 on the rear faces of the mold halves l4 and I8 and projecting into the path of flow of air over these rear faces.

In the cooling of molds by air as above described it is preferable that the cooling air in being delivered to the rear face of a mold half be initially directed at that portion of the nrold half subject'to the absorption of the greatest amount of heat from the molten metal during a casting operation. While in the broader aspects of the present invention the construction is of such flexibility, as by providing any required number of openings IIO positioned as required to obtain this effect as will hereinafter be more apparent, particularly where two or more objects are being cast simultaneously between each cooperating pair of molds, in the particular construction of the mold halves I4 and I8 shown by way of i1- lustration, the mold halves I4 and I8 have been formed to enable a single triangularly shaped pan-like member of the general character illustrated in Fig. 8 to be cast in the cavity ll between them. The pan-like figure shown in Fig. 8 may be assumed, as a matter of illustration, to be suitable for use as a paving block for highways and the like, its upper or exposed surface being provided with a plurality of upwardly projecting ribs arranged in groups extending transversely with respect to one another for the purpose of providing an anti-skid surface therefor.

It may also be assumed for the purpose of illustration that only one such block'as illustrated 40 in Fig. 8 will be cast at one time between each pair of mold halves 14 and I6 and, accordingly,

the depression or cavity 11 formed between the mold halves I4 and I8 will preferably be centrally located with respect thereto as illustrated 45 in the drawings. In such case the opening IIO being located centrally of each plate I08 will direct the flow of incoming air centrally with respect to each of the mold halves l4 and I8 and thus initially into that area of the mold halves 50 which will receive the greatest amount of heat from the molten metal received inthe mold cavity 11. It will, however, be observed that with the particular conformation of the mold cavity 11 required to form the block shown in Fig. 8 the 55 greatest amount of metal in the mold cavity will be adjacent the lower edges thereof and, accordingly, the corresponding portions of the mold halves 14 and 16 will preferably receive a greater amount of cooling air than the upper portion 60 thereof which will be less highly heated in the casting operation. This effect is obtained in accordance with a further phase of the present invention which is particularly brought out in Figs. 3 and 5.

As indicated in Figs. 3 and 6 the above described .effect is accomplished by the employment of a pair of battle members H4 in connection with each opening IIO. These baflle members II4 each comprise a plate-like member se- 7 cured to the outer face of each of the plate members I08 in cooperating relation with respect to the side edges of the opening H0. The plate members or baiiles II4 are preferably readily adjustable with respect to the edges of the coop- IIO so as to enable the effective area and shape of the opening IIO to be varied. While any suitable means may be provided for adjustably supporting the baflle members II4 on their corresponding plate I08, one acceptable method is shown and which comprises the provision of slots H8 in the baffle members H4 and wing nuts II8 received on studs I20 fixed to the corresponding plates I08 and projecting through the slots I I8. The studs I20 are sufficiently loosely received in the slots I I8 as to permit the bafile members I I4 to be moved bodily inwardly or outwardly in parallel relation with respect to the corresponding edges of the opening H0, or to be tilted with'respect thereto as illustrated in Fig. 6, so as to cause, for instance, agreater restriction of the opening IIO adjacent the top thereof than at the bottom thereof. Preferably each of the baffle members H4 is provided at its inner edge with an outwardly extending flange I22, the flanges I22 preferably being curved outwardly away from each other so as to provide a more or less venturi-like passageway between them more favorable to the flow of air therebetween without restriction.

In order to withdraw the airfrom the crosschamber I04 in the stationary supports 80 a passageway I24, best illustrated in Figs. 1 and '7, is formed integrally with the cord 22 in communication with the cross-passage I04 and extends through and opens upon the joint between it and the adjacent cord 22. As best illustrated in Figs. 1 and 7 the cords 22 at adjacent ends are provided with vertically extending cooperating flanges I26 which are rigidly secured together'by means of bolts I28. Below the flanges I26 the adjacent ends of the cords 22 are formed to provide a pocket I30 for relatively close reception of the end of the corresponding hollow arm 20. Within the pocket I30 the arm 20 is provided with an opening I32 which registers with the passage I24 and thus communication is established between the hollow interior of each arm 20 and the cross-passage I04 of a corresponding fixed support 80. It will be recalled that it has been previously explained that the hollow interior of the arms 20 are in open communication with the interior of the central drum member I4 of the turrets.

As best illustrated in Figs, 2 and 4 the crosspassage I04 of each movable mold section 84 is inopen communication with the interior of a tube I34 which extends radially inwardly therefrom with respect to the axis of the turrets. Each tube I34 is flxed with respect to its corresponding movable mold section 84 and, as illustrated in Fig. 2, its inner end projects relatively loosely through an opening I36 provided therefor at the inner end of the cooperating arm 20 and in the periphery of the drum member I4, so that the cross-passage I04 of each movable mold section 84 is communicated with the hollow interior of the drum I4.

From the construction of the central portion of the turret as heretofore described it will be understood that the hollow interior of the drum I4 is in open communication with the interior of the stack or flue 48 which is stationary. The stack 48 communicates with a suitable source of suction which may, for instance, be a suitable type of centrifugal fan (not shown) and which, when in operation, will maintain the interior of the flue 48 under a sub-atmospheric pressure of desired value. Accordingly, it will be understood that with the construction thus far described relatively cold or at least unheated air will be drawn through the opening H in the plate member I08 of each of the mold sections 80 and 84, this air will bathe the inner surfaces of the mold halves I4 and I6, will then pass outwardly through the chambers I02 to cross-chambers or passages I04 and will then be drawn through the passages described to the interior of the drum member H4 and exhausted therefrom through the stack or flue 48. As it is preferable to permit this flow of cooling air to continue during the complete revolution of the turret in order to obtain a maximum cooling effect on the mold halves and thus aid in enabling the speed of production of the machine to be increased, no means are shown forinterrupting this flow during any particular angular phaseof movement of the turret.

As previously explained the movable mold section 84 is maintained in cooperating relationship with respect to .the fixed mold section 80 during that phaseof rotation of the turret during which the molten metal is cast into the mold cavity II and until a sufficient time has elapsed to insure the molten metal having solidified to such an extent as to make it feasible to open the mold and discharge the part thus cast from between them. The means for effecting this movement of each movable mold section towards and from its corresponding fixed mold section together with means so constructed and arranged as to effect such movement at the desired point in the path of rotatable movement of the turret, will now be described in detail.

As best shown in Figs. 1 and 2 a bracket member I40 extends between and is supported on the upper surfaces of each adjacent pair of arms 20 adjacent the central drum I4, and each bracket I40 is provided with an upstanding flange I42 to the rear face of which the forward end of an air cylinder I44 is fixed thereby to support the cylinder. The air cylinders I44 are of a conventional type each of which includes a piston I46 having fixed thereto a piston rod I48 which projects outwardlytherefrom through the outer end of the cylinder I44 and flange I42. The cylinders I44 are so arranged that their respective piston rods I48 are arranged in radial relation with respect to the axis of rotation of the turret and so that the axis of each piston rod I 48 extends centrally with respect to the radial center line of its corresponding mold assembly.

The movable section 84 of each mold assembly has fixed to its inward face as by means of screws I50 a yoke I52 and which, as best illustrated in Figs. 3 and 4, is provided with a central bore I54 arranged radially with respect to the axis of rotation of the turrets and in axially aligned flange I56 and washer I60 are so spaced as to accurately receive the thickness of the correspondingportion' of the yoke I52 therebetween andto permit the outer end of the, corresponding piston rod I48 and appreciable amount of free play laterally in the bore I54 without permitting more than a very limited amount of play of the yoke I52 axiallyrof the piston rod I48. This arrangement'insures that the entire weight of the movable mold section is carried on the rails 94 through the rollers 82 without endangering binding of the piston rod I48 in its cylinder.

A- control -valve structure of conventional construction indicated generally at I66 is provided for each cylinder I44 and is fixed with respect to its corresponding cylinder I44 in adjacent relationship upon the exterior surface of the central housing member 26. Each valve structure I66 is connected by means of a pipe line I68 with the forward end of the corresponding cylinder I44 and connected by a pipe line IIII with the rear end of its corresponding cylinder I44. Each valve is also provided with an air exhaust line or pipe III which, as shown in Fig. 2, discharges into the interior of the drum I4. The valves I66- are interiorly in communication with the annular .duct 28 in the member 26 so as to receive a supply of compressed air therefrom. Each valve'I66 is provided with an operating arm 2, the outer end of which supports a roller I'I4 as best shown in Fig. 2. As will be appreciated by those skilled in the art when the arm I72 isat one limit of its movable position compressed air from the duct 28 will be admitted to one end of the cylinder I44 while air will be permitted to escape from the oppositeend thereof through the pipe HI, and when'the arm H2 is at the opposite limit of its movable position the reverse of these conditions will obtain. As will also be appreciated, when air under pressure is introduced into the inner end of the cylinders I44 the corresponding pistons I46 will act through the corresponding piston rods I48 to move the corresponding movable mold sections radially outwardly with respect to the axis of the turrets and to place the mold sections in closed or pouring position, and that when compressed air is introduced into the forward end of each of the cylinders I44 and airis permitted to be exhausted sections so as to permit discharge of the article cast between such mold sections and conditioning of the mold sections for the next casting operation.

In order to effect an automatic actuation of the movable mold sections in properly timed relation to the rotatable position of the turret the following mechanism is provided. The stationary ring 46 which supports the stack 48 at the center of the turret is provided in its exterior surface with an annular T slot I80 therein. Secured to the outer face of the ring 46 by means of bolts I82 the heads of which are received within the T slots I80 is a pair of brackets I84 projecting radially outwardly from the ring 46. Each of the brackets I84 has secured to its lower face a cam member I86. The cam members I86 are secured to the brackets I84 by means of a pair of bolts I88 extending through a radial slot I90 in the corresponding bracket I86, the construction thus permitting the cam members I86 to be adjusted radially of their corresponding brackets I84. The

cam members I86 as best shown in Fig. 1, have a V-shaped face or operating surface I92. for engagement with the rollers I14 on the operating arms "2 of thevarious valves I66. One of the cam members I86 is arranged so that its V surface I92 converges in a radially outwardly direction so that upon engagement with the roller "4 of any valve arm "2 the valve arm will be caused to move to the outer limit of its movable position, and the other cam member I88 is arranged with its V surfaces I92 converging in an inwardly direction so that when it engages the rollers I'll of the valve arms I12 these arms will be caused to move to the inward limit of their movable position. By this means as the turret revolves and the various rollers I12 successively engage first one of the cam members I" and then the'other.

cam I86 the valves will be operated first to effeet a closing of the mold sections and then will be operated to separate the mold sections. The particular point at which the mold sections are opened or closed may be readily varied by simply shifting the brackets I84 circumferentially of the ring 46, this being readily accomplished because of the manner of securing the brackets I to the ring 46 by the use of the T slots I80.

From the foregoing it will be understood that in accordance with the present invention a permanent mold machine is provided in which means are provided for rotating the turret at diflerent rates of speed although driven by an electric motor of constant speed, so as to accommodate the machine to the highest rate of production commensurate with the size and characteristics of the article being cast; it provides a mold construction'particularly useful in connection with a permanent mold machine but which may be employed singly, if desired, and which because of its novel arrangement for artificially cooling the same permits unusual rapidity in repeated casting operations; and provides a novel arrangement for mounting and operating the various movable mold sections in a permanent molding machine together with numerous novel details of construction throughout the same.

=40 departing from the spirit or substance of the Formal changes may be made in the specific embodiment of the invention described without broad invention, the scope of which is commensurate with the appended claims.

What I claim is:

1. In combination, a permanent mold part having a recessed rear face, a member cooperating therewith to form a chamber bounded by the walls of said recess, said member having an opening therein for the flow of air into said chamber, and bale means associated with said member operable to vary the effective area of said opening whereby to modify the flow of air through sa.d opening.

2. In combination, a permanent mold part having a recessed rear face and a member associated therewith forming a chamber between it and said recessed face, said member having an opening therein for the flow of air into said chamber, a baffle carried by said member in cooperative relation with respect to the margins of said opening, and means cooperating between said bailie and member operableto adjustably secure said baffie in any one of a plurality of different positions on said member whereby, to enable the effective shape and area of said opening to be varied by adjusting the overlapping relation of said baflle with respect thereto. 3.- In combination, a mold part having a recessed rear face, a member cooperating with said rear face whereby to form a chamber between it and said recessed face, said member having an opening therein for the flow of air into saidchamber, baille means adjustably secured to said member in cooperative andin partially overlapping relation with respect to said opening whereby to enable the effective shape and area of said opening to be varied, and a flange on said baiile member for modifying the fiow of air through said opening by forming a guiding means therefor.

JOSEPH L. DOSTAL. 

